我有一个组合框，当＆＃34; Minor＆＃34;点击总费用应保持值：180

Question

mTypeList.addActionListener(new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent event)
    {
        String s = (String) mTypeList.getSelectedItem();

        switch (s) {
            case "Minor":
                totalCharge = 180;
                JOptionPane.showMessageDialog(null,"You have been charged $180 to have 'Minor' maintenance work");
            break;

            case "Major":
                totalCharge = 320;
                JOptionPane.showMessageDialog(null,"You have been charged $320  to have 'Major' maintenance work");
            break;
         }
    }
});